It's one of those things that we ALWAYS think about doing but never quite get around to--even though we know how important it can be in situations ranging from a house fire to a toxic gas leak to a natural disaster.

In order to make sure we do it right, we contacted Cheryl Luptowski, home safety expert at NSF International, a not-for-profit public health and safety organization. Here are her picks for the top 10 things that should be in everyone's emergency stash.

1. Water. You should have enough water to last three days–figure a gallon per person per day. This will not only be useful for drinking, but also sanitation and food prep. Pack a bit extra if you have pets.

4. Tools. A screwdriver, a hammer, and a wrench. Will be handy in the event you need to turn off a gas or water line. Also, toss a manual can-opener in there. Those canned food items aren’t too useful if you can’t get them open.

5. Clothing. A change of clothing, including comfortable walking shoes and underwear, for everyone in the family.

6. Blankets. One blanket per family member in case it’s needed for warmth or shelter.

7. Flashlight and backup batteries. Obviously hugely important if you’re trying to safely navigate during a power outage.

8. A whistle. Any whistle that’s loud enough to travel a decent distance (probably not the one your kid got as a prize at the arcade!) will do the trick.

9. Important documents. Copies of each family member’s birth certificate, a back-up credit card, a list of important phone numbers, and key insurance information should be stashed in a waterproof plastic bag or envelope.

10. Any other items key to your family’s health/sanity: A week’s worth of any regular prescription medications, eyeglasses or contacts/solution, diapers, formula, a back-up “blankie,” etc.

Store the goods in a plastic container on rollers (found with the storage containers in mass retailers such as Wal-Mart) and stash it in a common area in your home.

Luptowski recommends a closet by the front door. One place to avoid: The garage, where fumes could contaminate food items (or critters could mooch!).

At least once a year, go through your kit and update food and water (even non-perishable items lose their freshness) as well as clothing (based on the season, you might need different items, and your kids might need updated sizes).